Krill Oil Vs Fish Oil

After multivitamins and multi-mineral supplements, the third most popular dietary supplement in the world is fish oil. Derived from fatty fish such as anchovies, mackerel, sardines and salmon, fish oil attributes its popularity to its wide array of health benefits ranging from combatting inflammation to boosting heart and brain health.

The superstar elements that everyone goes for in fish oil are omega-3s, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In fact, getting their dose of omega-3s is the reason why most people consume fish.

Nevertheless, there’s a new superstar in town known as krill oil that promises to give just as good, if not better, omega-3 punch. Krill oil also boasts of containing EPA and DHA.

In light of such developments, which one is better? Fish oil or krill oil? This article aims to find out.

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What is Krill Oil?

Krill are tiny, reddish pink, shrimp-like crustaceans, and are the primary diet of the world’s largest animal; the blue whale. In fact, krill literally means ‘whale food’ in Norwegian.

Currently, there are at least 85 recognized species of krill. However, most krill oil is derived from one species, the Antarctic Krill. Krill oil is one of the best sources of omega-3 fatty acids, DHA and EPA. However, their fatty acids are structurally different from those of fish oil, and it appears like this affects the way the body utilizes them.

Additionally, while fish oil has a gold or yellow appearance, krill oil has a reddish hue, emanating from an antioxidant known as astaxanthin. In addition to the EPA and DHA fatty acids, krill oil also contains a host of other essential fatty acids as well.

What is Fish Oil?

This is an oil that is derived from the fatty tissue of fish. Fish oil contains both DHA and EPA fatty acids. Most fatty fish, however, do not naturally produce omega-3s. Instead, they accumulate them through the consumption of diets rich in omega-3s such as microalgae. 

Importance of Omega-3 Fatty Acids

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The human body cannot naturally produce fatty acids. As such, you need to get them from your diet. The omega-6 to omega-3 ratio in your body is of vital importance since it has a significant effect on your overall health. One study analyzed the effects of this ratio and found out that an omega-6 to omega-3 ratio of 4:1 reduced the general risk of dying by 70 percent.

Other benefits include:

Brain Health and Development

Studies show that women who are low in DHA fatty acid are at a higher risk of bearing children with poor neural development as well as cognitive disorders.

In adults, omega-3s are useful in enhancing the process of creating neurons (neurogenesis). High levels of neurogenesis are associated with improved cognitive function as well as reduced white and gray brain tissue loss as you age.

Additionally, omega-3s help reduce inflammations in the brain.

Heart Disease

Heart disease is one of the deadliest conditions afflicting first-world countries. However, taking omega-3s has been found to reduce your susceptibility to cardiovascular illnesses significantly.


By consuming diets that are rich in omega-6s but deficient in omega-3s, one is likely to develop chronic inflammation. Chronic inflammation, on the other hand, is associated with issues such as heart conditions, joint pain, dementia, Alzheimer’s, among a host of other problems.

Consistent intake of omega-3s, however, has been found to lower the overall inflammation in the body.

Lean Muscle Mass

Consuming diets that are rich in omega-3 fatty acids has been found to increase your overall lean muscle mass. This is because omega-3s enhance muscle protein synthesis while simultaneously lowering the rate of muscle protein breakdown. 

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Difference between Fish Oil and Krill Oil

Anytime that you consume seafood or take omega-3 supplementation, you get a dose of EPA and DHA omega-3 fatty acids which help in:

  • Improving your cholesterol levels
  • Reducing inflammation and
  • Decreasing the risk of your platelets, forming dangerous clots. 

However, there are some key differences when it comes to the source of those omega-3s. Krill oil is arguably better for the following reasons: 

1. Contains Extra Nutrients

In addition to omega-3 fatty acids, krill oil also contains vitamins A, E, B12 and folate. Additionally, since part of the krill’s diet is marine lichen, krill oil also contains astaxanthin. Astaxanthin is an antioxidant that has neuroprotective properties. As such, it works to reduce damage to the brain as well as the central nervous system from oxidative stress.

Krill oil, unlike fish oil, provides phospholipids and antioxidants, which boost its stability and bioavailability as well as provide us with health benefits. Also, whereas DHA and EPA fatty acids in fish oil are usually in the form of re-esterified triglycerides, in krill oil, they are either unbound or in phospholipid-bound form.

2. Might Have Fewer Contaminants

As compared to most fish, krill are a lot smaller in addition to being much lower in the marine food chain. As a result, they tend to contain lower levels of mercury and other toxins. Additionally, krill oil goes through a more stringent testing process.

3. Absorbs Better

When given in equivalent dosages, DHA and EPA fatty acids from krill oil have been found to be absorbed better in the body than those from fish oil. In a comparative study of fish oil and krill oil, the results revealed that krill oil increases the amount of circulating omega-3 fatty acids by about 33 percent more than fish oil.

Another study’s findings revealed that a dose of krill oil that was 40 percent less than that of fish oil generated the same levels of omega-3 fatty acids as the fish oil dose. The inference, therefore, was that DHA and EPA in krill oil are absorbed more efficiently.

4. Brain and Heart Health

A scientific trial comparing the effects of fish oil and krill oil on cardiovascular health discovered that in addition to boosting various markers of heart health, krill oil also reduced fasting glucose. This effect reduces the risk of heart disease.

Also, in addition to improving the bioavailability of omega-3s, krill oil’s phospholipids also contain a host of cellular and brain benefits due to their antioxidant and anti-inflammatory properties.

Studies done on humans to study the effects of krill oil reveal that this oil also reduces C-reactive protein, which is an anti-inflammatory marker that is associated with cardiovascular problems. The researchers went on to say that krill oil is more effective at reducing inflammation and improving insulin sensitivity than fish oil.

Additionally, fish oil has been found to increase the activity in cholesterol synthesis pathways. Krill oil, on the other hand, reduces the activity of these pathways. This means that krill oil is the better option if you are looking to lower your cholesterol.

A study on genomes discovered that fish oil changed the expression of four genes, while krill oil altered the expression of 13 genes, including genes that are involved in the metabolism of cholesterol, lipids and glucose.

Krill Oil Risks

krill oil

While there aren’t any documented cases of adverse effects from krill oil, some of its potential effects include:

  • A fishy taste
  • Perspiration that smells like fish
  • Upset stomach
  • Diarrhea
  • Heartburn and gas

Additionally, the omega-3s found in both fish and krill oil may contribute to blood thinning. As such, if you are on medication for blood-thinning or are using non-steroidal anti-inflammatory drugs, it is wise to first consult with a physician before taking krill oil.

The same goes if you are allergic to crustaceans, shellfish or seafood in general.

Nonetheless, while krill fisheries do not fish at extreme levels like those used to harvest large fish, some forms of krill fishing can harm the ecosystem. As such, it is essential to note whether the company providing you with fish oil or krill oil utilizes sustainable harvesting practices.

Fish Oil Risks

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Fish oil shares the same effects as krill oil, such as unpleasant taste and stomach problems. It can also contribute to blood thinning. Again, if you are allergic to seafood, then it is best to consult a doctor before using the supplement.

Additionally, fish tend to have high levels of toxins as they are larger.

The biggest problem with fishing for fish oil due to its omega-3 content, however, is the likelihood of overfishing. As such, when it comes to environmental sustainability, fish oil might not be the best source for omega-3s. 

Fish Oil vs. Krill Oil: The Verdict

In their own rights, krill oil and fish oil are both excellent sources of omega-3 fatty acids, with their health benefits having the backing of extensive scientific research.

However, when pitted against each other, krill oil offers more benefits that come from its extra nutrients such as phospholipids and antioxidants. Additionally, those phospholipids as well as astaxanthins that are in krill oil help enhance its shelf-life in addition to helping your body absorb krill oil better than fish oil.

In terms of environmental sustainability, krill oil is the better option since the harvesting of krill does not have as much of an impact on the ecosystem like fishing does.

Ultimately, your goal is to have a daily healthy dose of omega-3s. While fish oil can offer you that, krill oil provides you the same and more. Have you tried fish oil or krill oil? Try them and let us know what you think.

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